Policy information sourced from the Guildford Local Plan: Strategy and Sites
P4: Flooding, flood risk and groundwater protection zones
Flood zones in the borough of Guildford are defined based on definitions contained within national planning practice guidance and the Council’s Strategic Flood Risk Assessment (Level 1).
Development in areas at medium or high risk of flooding, as identified on the latest Environment Agency flood risk maps and the Council’s Strategic Flood Risk Assessment, including the ‘developed’ flood zone 3b (functional floodplain), will be permitted provided that:
- the vulnerability of the proposed use is appropriate for the level of flood risk on the site
- the proposal passes the sequential and exception test (where required) as outlined in the NPPF and Government guidance
- a site–specific flood risk assessment demonstrates that the development, including the access and egress, will be safe for its lifetime, taking into account climate change, without increasing flooding elsewhere, and where possible, will reduce flood risk overall
- the scheme incorporates flood protection, flood resilience and resistance measures appropriate to the character and biodiversity of the area and the specific requirements of the site
- when relevant, appropriate flood warning and evacuation plans are in place and approved and
- site drainage systems are appropriately designed, taking account of storm events and flood risk of up to 1 in 100 year chance with an appropriate allowance for climate change.
Development proposals in the ‘developed’ flood zone 3b will also only be approved where the footprint of the proposed building(s) is not greater than that of the existing building(s) and there will be no increase in development vulnerability. Proposals within these areas should facilitate greater floodwater storage.
With the exception of the provision of essential infrastructure, ‘undeveloped’ flood zone 3b will be safeguarded for flood management purposes.
All development proposals are required to demonstrate that land drainage will be adequate and that they will not result in an increase in surface water run-off. Proposals should have regard to appropriate mitigation measures identified in the Guildford Surface Water Management Plan or Ash Surface Water Study. Priority will be given to incorporating SuDs (Sustainable Drainage Systems) to manage surface water drainage, unless it can be demonstrated that they are not appropriate. Where SuDs are provided, arrangements must be put in place for their management and maintenance over their full lifetime.
Development within Groundwater Source Protection Zones and Principal Aquifers will only be permitted provided that it has no adverse impact on the quality of the groundwater resource and it does not put at risk the ability to maintain a public water supply.
For more information please see the Local Plan